1. Field of the Invention
The present invention relates to a method of and an apparatus for processing a photographic photosensitive film in a film producing and packaging system for unreeling a film roll of elongate photographic photosensitive film, cutting the elongate photographic photosensitive film to a film of given length, winding the cut film on a spool, and placing the wound film into a film cartridge.
2. Description of the Related Art
For producing and packaging a photographic photosensitive film, it has been customary to perform various steps including the steps of producing a film of given length, winding the film, placing the wound film into a film cartridge, and inserting the film cartridge into a case.
These various steps are carried out by a facility comprising a film supply unit for unwinding a film roll and cutting the unwound film to a film of given length, a film coiling unit for coiling the film of given length on a spool thereby to produce a film coil, a cartridge producing unit for staking a cap on an end of a tubular cartridge blank sheet thereby to produce a cartridge with one open end, an assembling unit for inserting the film coil into the cartridge and staking another cap on the open end of the cartridge thereby to produce an assembled cartridge, and an encasing unit for placing the assembled cartridge into a case and attaching a case cap on an open end of the case thereby to produce a packaged product.
If the above facility stops its operation due to any of various failures or there is a leakage of light into a dark room in the facility, then the photographic photosensitive film tends to be made defective, e.g., damaged or exposed to light. When a certain photographic photosensitive film is made defective, it has been the customary practice for the operator to discard all photographic photosensitive films in the same batch as the defective photographic photosensitive film. However, this practice is highly uneconomical.
There has been known a process, as disclosed in Japanese laid-open patent publication No. 6-266059, of detecting whether a photographic photosensitive film is acceptable or not, shifting a defective film signal indicative of any detected defective photographic photosensitive film in synchronism with the movement of the photographic photosensitive film, and, when the defective film signal is shifted in association with a switching position for a delivery path capable of discharging a photographic photosensitive film out of the system, switching the delivery path to automatically discharge a defective photographic photosensitive film out of the system.
Depending on the facility suffering a failure or the details of such a failure, a photographic photosensitive film may be subjected to a defect in a substantially long range, and it is highly time-consuming to automatically discharge a long defective film. Furthermore, if a photographic photosensitive film is twisted or jammed due to a failure of the film delivery system, then the photographic photosensitive film cannot be delivered smoothly along the delivery path.
The elongate photographic photosensitive film unreeled from the film roll has a plurality of perforations defined at spaced intervals in side edges thereof. When the photographic photosensitive film is to be trimmed after it has been fed to a cutting position by a predetermined length, one of the perforations may possibly be located in the cutting position. An end of the photographic photosensitive film which is to be trimmed in the cutting position will serve as a tongue of given length that projects out of an assembled cartridge. If a perforation in the film is positioned at the leading end of the tongue, then it tends to cause trouble when the film is wound in a camera. Consequently, the cartridge whose film tongue has a perforation in its leading end is poor in quality and is not acceptable as a marketable product. Because the possibility that a perforation in the film will be positioned at the leading end of the tongue is high, the percentage of defective assembled cartridges is large. This is not economical since a number of expensive cartridges have to be discarded.
Assembled cartridges produced by the assembling unit are tested by pulling projecting film ends, i.e., tongues, to measure the resistance to the pull. Japanese patent publication No. 5-55022, for example, discloses a device for measuring the resistance to the action to pull a projecting film end from an assembled cartridge.
According to the disclosed device, while an assembled cartridge is being held by an inspection turret which is continuously rotated, the resistance to the action to pull a projecting film end from the assembled cartridge is measured by a measuring unit associated with a film pulling mechanism. The measuring unit measures the resistance while the assembled cartridge is being continuously delivered.
When assembled cartridges are produced by the assembling unit, they are inspected in various tests in addition to the measurement of the resistance to the film end pulling action. For example, assembled cartridges are inspected to check if a cap is staked on an open end of the cartridge in which a film coil has been inserted, and also to check if the cap is properly staked on the open end.
Such inspecting processes need to be carried out independently in respective stations in the assembling unit. Accordingly, the assembling unit requires a relatively large working space and is highly complex in structure. Because the inspecting processes are considerably time-consuming, they are not efficient to perform.
It is a general object of the present invention to provide a method of processing a photographic photosensitive film in a manner to be able to easily and quickly discard unacceptable portions of the photographic photosensitive film which are defective due to facility failures.
A major object of the present invention is to provide an apparatus for processing a photographic photosensitive film in a manner to be able to reliably discard, with a simple arrangement, defective film portions including joints between photographic photosensitive films.
Another major object of the present invention is to provide a method of and an apparatus for processing a photographic photosensitive film while reliably and easily detecting, with a simple arrangement, whether a perforation defined in a side edge of the photographic photosensitive film is located in a cutting position or not, when films of given length are produced from the photographic photosensitive film that is unreeled from a film roll.
Still another major object of the present invention is to provide a method of and an apparatus for processing a photographic photosensitive film while efficiently performing various inspecting processes including a process of measuring the resistance to a pull on the photographic photosensitive film, in a reduced space and with a simple arrangement.